2016 SPRING FINAL Flashcards
MAS is _____ proportional to pt. dose
Directly
KVP is main controlling factor of __1__ but it also affects density mainly because it controls __2__.
- Contrast
2. Scatter
Inverse Square Law:
If you double the distance, you cover __1__ the area with __2__ the intensity. If you cut distance in half, you cover __3__ the area with __4__ the intensity.
- 1/4
- 1/4
- 4x
- 4x
30% rule deals with
MAS
15% rule deals with
KVP
30% rule states in order to make visible change in __1__ one must increase or decrease __2__ by 30%
- Density
2. MAS
15% Rule: BELOW 90 kV 1. +10 kV=\_\_\_\_\_\_\_ 2. -10 kV=\_\_\_\_\_\_\_ ABOVE 90 kV 3. +15 kV=\_\_\_\_\_\_\_ 4. -15 kV=\_\_\_\_\_\_\_
- Cut mAs in 1/2
- Double mAs
- Cut mAs in 1/2
- Double mAs
Increase OID=______ density
DECREASED (due to air gap and scatter bypassing IR)
Increased screen speed= 1. MAS 2. Pt. Dose 3. Detail Decreased screen speed: 4. MAS 5. Pt. Dose 6. Detail
- Decrease
- Decrease
- Decrease
- Increase
- Increase
- Increase
Increased collimation=_____ density
Decrease
Decreased collimation=______ density
Increased
As part density increases, IR density __1__. As part density decreases, IR density (RE) __2__.
- Decreases
2. Increases
Degree of differences in density
Contrast
High kV:
- _____ scale
- _____ contrast
- _____ colors
- _____ latitude
- _____ pt. dose
- _____ scatter
- ______ penetration
- Long
- Low
- Many
- Wide
- Decreased
- Increased
- More
Low kV:
- ___scale
- ___ contrast
- ___ colors
- ___ latitude
- ___ pt. dose
- ___scatter
- ___ penetration
- Short
- High
- Few
- Narrow
- Increased
- Decreased
- Less
Increased grid ratio= __1__ contrast ( __2__scatter)
- Increased
2. Less
Decreased grid ratio=__1__ contrast ( __2__ scatter)
- Decreased
2. More
Increased collimation=__1__ contrast.
Decreased collimaton=__2__ contrast
- Increased
2. Decreased
Additive pathology requires what in technique?
Increase
Destructive pathology requires what in technique?
Decrease
3 geometric factors that control recorded detail:
1.
2.
3.
- Focal Spot (Small)
- OID (short)
- SID (long)
As FS increases, unsharpness (penumbra) __1__ and recorded detail (umbra) __2__.
- Increases
2. Decreases
As FS decreases, unsharpness (penumbra) __1__ and recorded detail (umbra) __2__.
- Decreases
2. Increases
As SID increases, unsharpness (penumbra) __1__ and recorded detail (umbra) __2__.
- Decreases
2. Increases
As SID decreases, unsharpness (penumbra) __1__, recorded detail (umbra) __2__.
- Increases
2. Decreases
As OID increases, unsharpness (penumbra) __1__, and recorded detail (umbra) __2__.
- Increases
2. Decreases
As OID decreases, unsharpness (penumbra) __1__ and recorded detail (umbra) __2__.
- Decreases
2. Increases